The main objective of the proposed research is to develop effective and efficient methods of smoking control for dependent smokers who are unable to quit by themselves. Emphasis will be on developing effective strategies for the enduring maintenance of nonsmoking. A second objective is to increase understanding of the processes involved in quitting and maintenance of non-smoking. A controlled outcome study evaluating the effectiveness of nicotine fading (brand switching) and relapse prevention training was conducted. Long term follow-up data are now being collected. The utility of Bandura's self-efficacy theory in explicating relapse was investigated in clients from two smoking control programs. Post treatment self-efficacy ratings predicted time to relapse (multiple R equals .69) and the class of situation in which relapse occurred (weighted kappa equals .89). The effects of a counselor's own smoking status on their credibility to potential smoking clients was investigated in a design that also considered counselor experience level and preference for group versus individual treatment. Pilot work on the role of withdrawal reactions in relapse, and the role of the spouse or living partner in quitting efforts is also underway.